The reason for the effect of green coffee beans on weight loss lies in a compound present in unroasted and raw coffee beans called chlorogenic acid. Basically, what this compound does is it tells your liver to stop absorbing fat while accelerating your metabolism. But why can't you just consume green coffee in its raw form? Why does it have to be in the form of a supplement that you buy? The simple answer to this would be that pure green coffee beans are bitter and while dr. Ounce does say that when it comes to weight loss the more bitter the better, if you were to roast these beans, you would lose the chlorogenic acids. This is technically why if you need to lose weight and you want to try the new sensation as far as the weight loss industry is concerned, a supplement form of svetol green coffee bean extract is your only option.